https://www.circuitlab.com/circuit/gyu8ur/power-produced-by-circuit/ Where does the additional power come from? |
by zenos
October 14, 2012 |

Does this help? |
by signality
October 24, 2012 |

Thank you for replying to my question. I will have to study your response further. |
by zenos
October 25, 2012 |

One way of looking at it is that the power dissipated in resistive components as calculated by Energy is the sum of power over time. This is the integral of power which is the same as the area under the power curve. If the product of If the product of This is because pure inductors and capacitors store energy. Resistors do not. So the The "extra" power you see in your original sim appears because your sim does not show you what happens when the supply is turned on from zero: this happens before your sim starts. If you use one of the various possible methods to ramp up the supply from zero after your sim starts and then carefully study the area under the V*I curves for components around the circuit and you'll find that the integral of the reactive power through the inductor sums to zero. Actually given the limitations of the solvers in CL, the sum to zero may not be exact but you should get the idea. Also beware that real L's and C's are not ideal. They have various resistive losses that do dissipate real power so in real LC circuits energy does get lost in the circuit as heat. Except in superconductors ... but then you can argue that it takes a lot of energy to keep the superconductors cold enough to store the energy without losses ... :) Some basic background on power in AC circuits: |
by signality
October 26, 2012 |

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